10" x 28" or 28" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 12.5" X 30.5"] w18h18 + Product Details Size -

+ Product Details Size - 18"w X 6"h is the size for the duct opening measurement only

Experience noise-free airflow and a healthier environment thanks to our grille's innovative design

Metal Fab - A brand you can trust

actual front end outer dimensions are 25

Ideal for Walls & Ceilings: Designed for seamless installation in standard 14" X 12" duct openings

10" x 28" or 28" x 10" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 12.5" X 30.5"] w18h18 + Product Details Size -+ Product Details Perfect Fit & Easy Sizing Designed for a 10" x 28" or 28" x 10" duct opening (measured at the opening), with actual outer dimensions of 12. 5" W x 30. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 9. 75" x 27. 75" x 1" Premium Airflow Efficiency High performance cube core eggcrate design allows 95% airflow efficiency, reducing energy costs and maximizing HVAC system lifespan. Durable, Rust Free Aluminum